Perpustakaan Digital ITB
Three-Reactor Chemical Looping (TRCL) technologies have emerged as a promising route for low-carbon energy conversion due to their inherent capability to separating CO2 with NOx. However, the high cost of synthetic oxygen carriers (OCs) motivating the exploration of low-cost natural ore-based alternatives. In this context, Indonesian iron- and manganese-based ores provide a potentially abundant and economically viable oxygen carrier source. This study evaluates the performance of natural iron sand, pyrolusite, manganese ore, synthetic Fe2O3, MnO2, and Fe–Mn blended oxygen carriers in a biomass-based TRCL. Fe–Mn blending enhanced the performance, where Fe-ISMM15 achieved up to 93.10% carbon conversion and 0.918 Nm3/kg gas yield, indicating strong catalytic and oxygen transfer synergy between Fe and Mn phases. In the steam reactor, hydrogen production strongly depended on oxygen carrier composition. Fe-ISMM30 exhibits to be the best-performing natural OC (120.6 mL/gOC), followed by iron sand (30.4 mL/gOC) with moderate consistency across cycles. The presence of ash in the sawdust was also found to positively influence hydrogen production due to catalytic and supporting effect. As a result, hydrogen yield increased from 0.098 mol to 0.143 mol. Overall, the results demonstrate that Fe–Mn blended natural ore oxygen carriers provide strong synergistic improvements in chemical looping performance. From a carbon circular pathway system perspective, integration of CLHG with ammonia co-firing in coal power plants demonstrated strong decarbonization potential. At 80% ammonia co-firing, coal consumption was reduced from 340.36 ton/h to 75.44 ton/h (?78% reduction), while CO2 emissions decreased from 591.88 ton/h to 118.36 ton/h (?80% reduction). Life cycle assessment further showed emissions reduction from 941 to 493.5 kgCO2eq/MWh (?47.6% reduction). Techno-economic analysis indicated a rise in Levelized Cost of Electricity from 0.0775 to 0.593 USD/kWh, while hydrogen and ammonia production costs were estimated at 5.84–5.88 USD/kg H2 and 1,037–1,078 USD/ton NH3, respectively. Overall, the results demonstrate that Fe–Mn blended natural oxygen carriers significantly enhance chemical looping performance through strong synergistic effects, while biomass ash constituents further promote hydrogen production. Integrated TRCL-based systems offer substantial decarbonization potential, albeit with increased economic and energy penalties.